A Red Arrows pilot who died after the parachute on his ejector seat failed to deploy was the victim of a fault that would only happen "once every 115 years", a court heard.

South African-born flight lieutenant Sean Cunningham died after being ejected from his Hawk T1 aircraft during pre-flight checks at RAF Scampton in Lincolnshire in November 2011.

The parachute attached to the Mark 10B ejector seat - manufactured by the Martin-Baker Aircraft Company - did not deploy, leaving the 25-year-old to fall 200ft to the ground.

He later died in hospital.

Image:A Red Arrows Hawk T1, the same type of aircraft used by Mr Cunningham

Defence lawyer Richard Matthews told Lincoln Crown Court that the aircraft firm accepted responsibility for the "significant contribution and failings it has made" in relation to Mr Cunningham's death, having already agreed to pay £550,000 in prosecution costs

But he added that the Ministry of Defence (MoD) had assessed that such an incident was exceptionally rare.

Speaking on the second day of a two-day sentencing hearing, Mr Matthews said: "In the 1990s, what Martin-Baker had in place was a good system and it just failed in this instance.

"The MoD's assessment of the likelihood of a similar event such as this happening is that it would only happen once every 115 years."

Image:The RAF Red Arrows is one of the world's premier aerobatic display teams

Middlesex-based Martin-Baker describes itself on its website as a family-run business and the "world leader in the design and manufacture of ejection and crash-worthy seats".

The court heard on Monday that the company had "undoubtedly saved the lives of many pilots" since inventing the ejector seat, and after last month's guilty plea the firm revealed that its ejection seats had been used by 92 air forces in the past 73 years.

Mr Matthews added: "The ethos of the company from its inception is for the ejection seat to be a lifeboat that should operate effectively in every situation.

"Nobody can convey the sadness, regret and the apology on behalf of the company and all those who stand behind it. I know you will accept that it is in enormous."